ABSTRACT
I n t ro d u c t i o n Diacylglycerol (DAG) is a component of edible oils and fats that has been shown to have nutritional functions distinct from ordinary triacylglycerol (TAG) oil. Studies conducted to date suggest that the primary effect of the DAG oil is on the plasma triglyceride concentrations after ingestion of DAG oil compared with TAG oil. In 1993, it was reported that dietary DAG oil has the ability to reduce serum triglyceride concentrations in rats that consumed a diet containing 10% test oil ad libitum ( 1 ) . Serum triglyceride levels in rats were decreased with increasing amounts of DAG oil at the expense of TAG in the test oil. However, the mechanism of this phenomenon remains unclear. Serum triglyceride concentration is maintained in a balance of supply from the gastrointestinal tract, which is derived from the dietary fat mainly in the form of chylomicrons, and from the liver mainly in the form of VLDL and their clearance from the circulation, which is mediated by lipases. In this chapter, we summarize studies on the lymphatic secretion of chylomicron and fatty acid distribution to the portal circulation. In addition, some preliminary results on the differences in the clearance of lipoprotein formed after DAG oil vs. TAG oil ingestion are discussed.
